That fishy looking Buffalo Bill? (4)
I believe the answer is:
cody
'buffalo bill?' is the definition.
(I've seen this in other clues)
'that fishy looking' is the wordplay.
'that fishy' becomes 'cod' (type of fish).
'looking' becomes 'y' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'cod'+'y'='CODY'
Can you help me to learn more?
(Other definitions for cody that I've seen before include "Surname of Buffalo Bill" , "Buffalo Bill's surname" .)